1. Field of the Invention
This invention relates generally to levees and barriers for the control and containment of water in open channels or in naturally or artificially occurring bodies of water, or of water otherwise lying on the earth's surface, and more particularly it relates to levees and barriers of modular construction.
2. Description of the Prior Art
Floods can have a devastating effect, both in economic loses and in lives disrupted or lost. Numerous attempts have been made to solve the water containment and control problem, yet each solution is deficient in some area.
The most common solution for water control problems involves the use of earthen embankments or levees made of soil. While earthen levees are economical to install, the motion of the water causes rapid deterioration, as the levee has no structure or armor to protect it. Also, particularly in some soils, subsidence reduces the height of the levee over time. Because of subsidence and because of damage due to water and wave action, the initial financial investment vanishes as the earthen levee deteriorates over a period of a few years. Also, as there is no structure beneath the soil, during floods the soil beneath the foundation of the levee may weaken or even form a liquefied zone, undermining the stability of the levee. Additionally, because the earthen levee is generally triangular in cross section, the levee must be quite wide at the bottom to have enough stable soil at the top to withstand water motion. Furthermore, an earthen levee cannot be easily built while in a flood, emergency, or repair situation. For example, if a levee along a river is inspected and found to be substandard, an earthen levee cannot be built in the water of the river around the defective portion to allow full access to both sides for repair of the substandard section. It would be advantageous to have a water control or levee system that was sturdier and more long lasting, that preserved more of the initial financial investment, that provided more structure or anchoring to combat the weakening of the foundation of the levee, that did not require such a large base compared to the height, and that could be constructed while in a flooding or repair situation.
When the earthen levee height is limited by weak natural soils or reduced by subsidence, additional height can be gained by driving corrugated steel sheet piles into the levee crest to form a floodwall. This method does provide more structure, as the sheet piles can be driven deeper vertically for more stability. However, several problems remain. If the supporting earthen levee with the floodwall subside, it is not easy to raise the height. The soil beneath the foundation of the levee may still weaken, destabilizing the levee. Because the floodwall is typically built with the sheet piles driven into earthen embankments, the floodwall is still wide at the bottom, which is especially troublesome when space is limited as in a city or near structures. Nor can the floodwall be easily constructed to a partial height to provide some protection, and then, as finances allow, be finished to a full height, which would be beneficial.
Accordingly, there is an established need for an effective, sturdy, long-lasting levee and barrier system and module that provides more structure or anchoring to combat the weakening of the foundation of the levee, that preserves more of the initial financial investment after subsidence, that reduces the required base size, that can be readily constructed while in a flooding or repair situation, that is configured to allow more height to be quickly and easily added to the levee should the need arise, and that can be constructed to a partial height to provide partial protection until finances allow completion to a full height.